A capacitor bank is conventionally known as a circuit that can change a capacitance value.
Patent Document 1 discloses an LC-VCO as an LC oscillator that varies an oscillation frequency using a capacitor bank. The LC-VCO includes an inductor, an offset capacitor, a varactor capacitor, a transistor for obtaining a negative resistance, and bias resistors RTOP and RBTM of the circuit, where the circuit changes the oscillation frequency by varying the capacitance value of the varactor capacitor included in the capacitor bank.